UTX_UTY: The ubiquitously transcribed tetratricopeptide repeat (TPR) UTX_UTY group of proteins have orthologues from worms to humans, and contain a tetratricopeptide repeat in addition to the JmjC domain. This group also includes the JMJD3 proteins (which have been identified in humans and mice) that lack the TPR domain. The function of the UTX_UTY proteins is largely unknown, except for the observation that UTY contributes to male-specific antigens, which can lead to the sex-specific tissue-transplantation rejection response. The expression and function of the UTX/UTY/JMJD3 orthologues in lower eukaryotes remain uncharacterized. (1)